the result of the public's disagreement with the learned gentleman above quoted, Bion J. Arnold, the great electrical engineer and traction expert of Chicago was retained by the Rapid Transit Railroad Commission to make a second report upon the ventilation or lack of ventilation of the subway.
Diagram D
This report is also available to any investigator, for it is in the Library of the Public Service Commission at the Tribune Bldg., but the essence of it is found in the following exact transcripts: On page 1 the statement is made that: "when the subway was originally built no special provision was made for the disposal of the accumulative heat or for its positive ventilation." On page 7 it says: "The heat of the subway comes from the operation of the trains due to the fact that about 85% of the electric energy produced by the power plant which operates the road is dissipated in the subway in the form of heat. The amount of heat given off by the train operation in 24 hours in the subway between 96th St. and the Brooklyn Bridge approximates the heat liberated from burning directly in the subway two tons of coal at each of the twenty stations in this section, or a total of 40 tons during the 24 hours. The most available ways for reducing the temperature of the air in the subway are as follows: 1, Refrigeration; 2, Cooling by water; 3, Blocking the automatic louvres open and providing additional openings; 4, Frequent air changes by means of a centre wall and train movement. Now the opposite train movements churn and whip the air producing opposing pressures and a rotating effect of the air about the train. The result is that most of the air has no definite direction of travel and remains in the subway instead of being discharged through openings
